@Deprecated. Will be closed. Change Manager: Handle the completion of the source data save

@Deprecated. Will be closed.
We need to implement handler to react on the completion of source records save.

1. handler updates status for Snapshot and JobExecution entities,
2. handler calls ExecutionEngine to parse raw records (event bus call).
3. handler must remove all data stored in the Vertx context for this JobExecution and release all resources to prevent resources leaks.
4. handler must cover negative cases also

Acceptance critirea

• Handler reacts on completion of the source data save;
• ChangeManager interacts with MetadataService for getting and updating JobExecution statuses;
• ChangeManager interacts with mod-source-record-storage via REST for updating Snapshot statuses;
• Bussines logic is covered by unit tests.